1. Field of the Invention
The present invention relates to an optimal load distributing system in a power plant. In particular, it relates to a system that carries out optimal load distribution taking the fuel cost into account.
2. Related Art
In general, a power plant is composed of a plurality of units, and the operational plan of each unit is determined according to the total output designated by the load dispatching office. According to the prior art, the way of distributing the load among the units to achieve the total output depends on the experience of the operator, and the power transmission cost is not always minimized.
In recent years, electricity markets have been established, and power companies have been demanded to improve the operational efficiency. Thus, there is a demand for a feature that helps distribute the load among the units in such a manner that the transmission power cost for the total power designated by the load dispatching office is minimized.
Japanese Patent Laid-Open No. 2000-78750 discloses an idea of operation optimization. However, according to this idea, an optimization calculation is carried out in real time based on sensor information from the actual plant, and a sub-controller is operated in real time for each unit of the power plant to save energy and improve the efficiency.